mercury meltdown or links crossbow training? *recommendation thread no help*

i only can pick one 20$ game and i decided to narrow it down to these two. im leaning towards link's crossbow training but im thinking mercury because its a much longer game. the only time ive ever played a game in the roll the ball genre was that rollgoal minigame in zelda. i was being frustrated rather than having fun. is mercury like this game or should i get link's crossbow training?

dont ppl own either of these?

well since you only have 20 dollars i say get Mercury because i bought it yesterday and its pretty fun 16 levels and theres multiplayer so its pretty good for the price. Get the zapper if your getting Ghost Squad